Title :
Non-linear optics studies at the ESRF
Author :
Ropert, A. ; Farvacque, L.
Author_Institution :
ESRF, Grenoble, France
Abstract :
Third generation synchrotron light sources like the ESRF are characterised by a small momentum compaction in order to achieve a small horizontal emittance as well as by large sextupoles to correct the chromaticity and enlarge the dynamic aperture. Therefore the linear description of the optics is inadequate when considering the large excursions in momentum experienced by Touschek scattered particles. A good modelling of the non-linear behaviour is essential to better understand the limitations in the energy acceptance of the machine. Measurements of chromatic closed orbits, betatron tunes, and synchrotron frequency for momentum deviations up to ±4% show a very strong non-linear behaviour on the negative energy side. A comparison is made of the experimental data with predictions from tracking simulations. Possible sources of disagreement are discussed
Keywords :
accelerator magnets; electromagnets; electron accelerators; electron optics; storage rings; ESRF; Touschek scattered particles; betatron tunes; chromaticity; closed orbits; dynamic aperture; energy acceptance; linear description; momentum deviations; nonlinear optics studies; sextupoles; small horizontal emittance; small momentum compaction; synchrotron frequency; third generation synchrotron light sources; Apertures; Character generation; Compaction; Light scattering; Light sources; Nonlinear optics; Optical scattering; Particle scattering; Stimulated emission; Synchrotrons;
Conference_Titel :
Particle Accelerator Conference, 2001. PAC 2001. Proceedings of the 2001
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-7191-7
DOI :
10.1109/PAC.2001.987154
